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1.
Epidemiol Infect ; 150: e37, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35225193

RESUMO

The epidemic of tuberculosis has posed a serious burden in Qinghai province, it is necessary to clarify the epidemiological characteristics and spatial-temporal distribution of TB for future prevention and control measures. We used descriptive epidemiological methods and spatial statistical analysis including spatial correlation and spatial-temporal analysis in this study. Furthermore, we applied an exponential smoothing model for TB epidemiological trend forecasting. Of 43 859 TB cases, the sex ratio was 1.27:1 (M:F), and the average annual TB registered incidence was 70.00/100 000 of 2009-2019. More cases were reported in March and April, and the worst TB stricken regions were the prefectures of Golog and Yushu. High TB registered incidences were seen in males, farmers and herdsmen, Tibetans, or elderly people. 7132 cases were intractable, which were recurrent, drug resistant, or co-infected with other infections. Three likely cases clusters with significant high risk were found by spatial-temporal scan on data of 2009-2019. The exponential smoothing winters' additive model was selected as the best-fitting model to forecast monthly TB cases in the future. This research indicated that TB in Qinghai is still a serious threaten to the local residents' health. Multi-departmental collaboration and funds special for TB treatments and control are still needed, and the exponential smoothing model is promising which could be applied for forecasting of TB epidemic trend in this high-altitude province.


Assuntos
Modelos Estatísticos , Tuberculose/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Feminino , Previsões , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Análise Espaço-Temporal , Tuberculose/prevenção & controle , Adulto Jovem
2.
Zhonghua Zhong Liu Za Zhi ; 44(12): 1369-1375, 2022 Dec 23.
Artigo em Chinês | MEDLINE | ID: mdl-36575789

RESUMO

Objective: To explore the metabolite profile and metabolic pathways of newly diagnosed multiple myeloma (MM). Methods: Gas chromatography-mass spectrometry (GC-MS) was employed for the high-throughput detection and identification of serum samples from 55 patients with MM and 37 healthy controls matched for age and sex from 2016 to 2017 collected at the First Affiliated Hospital of Soochow University. The relative standard deviation (RSD) of quality control (QC) samples was employed to validate the reproducibility of GC-MS approach. The differential metabolites between patients with MM and healthy controls were detected by partial least squares discrimination analysis (PLS-DA), and t-test with false discovery rate (FDR) correction. Metabolomics pathway analysis (MetPA) was employed to construct metabolic pathways. Results: There were 55 MM patients, including 34 males and 21 females. The median age was 60 years old (42-73 years old). There were 30 cases of IgG type, 9 cases of IgA type, 1 case of IgM type, 2 cases of non-secreted type, 1 case of double clone type and 12 cases of light chain type, including 3 cases of kappa light chain type and 9 cases of lambda light chain type. The result of QC sample test showed that the proportion of compounds with the RSD of the relative content of metabolites < 15% was 70.21% obtained by the reproducibility of GC-MS experimental data, which implied that the experimental data were reliable. A total of 17 metabolites were screened differently with the healthy control group, including myristic acid, hydroxyproline, cysteine, palmitic acid, L-leucine, stearic acid, methionine, phenylalanine, glycerin, serine, isoleucine, tyrosine, valine, citric acid, inositol, threonine, and oxalic acid (VIP>1, P<0.05). Metabolic pathway analysis suggested that metabolic disorders in MM patients comprised mainly phenylalanine metabolism, glyoxylic acid and dicarboxylic acid metabolism, phosphoinositide metabolism, cysteine and methionine metabolism, glycerolipid metabolism, glycine, serine, and threonine metabolism. Conclusion: Compared with normal people, patients with newly diagnosed MM have obvious differences in metabolic profiles and metabolic pathways.


Assuntos
Cisteína , Mieloma Múltiplo , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Adulto , Idoso , Mieloma Múltiplo/diagnóstico , Reprodutibilidade dos Testes , Metaboloma , Metabolômica/métodos , Redes e Vias Metabólicas , Metionina , Serina , Fenilalanina , Treonina , Biomarcadores
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(1): 104-107, 2020 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-31914577

RESUMO

From 1987 to 2017, cardiovascular disease (CVD) had been ranking the first cause of death in Suzhou, and the mortality rate showed an upward trend annual percentage changes (APC=0.62%, P=0.001), while the standardized mortality rate showed a downward trend (APC=-2.65%, P<0.001). The probability of premature death of CVD declined consistently from 7.06% in 1987 to 2.00% in 2017 (APC=-4.45%, P<0.001). When the life expectancy was set at 70, the potential years of life lost rate (PYLLR) decreased from 6.35‰ in 1987 to 3.30‰ in 2017, and the standardized PYLLR decreased from 7.30‰ to 2.68‰. When the life expectancy was set at 75, the PYLLR decreased from 10.12‰ to 5.19‰, and the standardized PYLLR decreased from 11.44‰ to 3.88‰. With the increase of years, all PYLLR and standardized PYLLR showed a significantly downward trend (APC=-2.51%--3.89%, P<0.001).


Assuntos
Doenças Cardiovasculares/mortalidade , Expectativa de Vida/tendências , Mortalidade Prematura/tendências , China/epidemiologia , Humanos , Probabilidade
4.
Phytopathology ; 107(1): 92-99, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27571309

RESUMO

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is a destructive disease in wheat. A population consisting of 229 F2 and F2:3 plants derived from the cross PI 672538 × L661 was used to evaluate the reactions to FHB. The FHB resistance data distribution in the F2 population indicates that some quantitative trait loci (QTLs) were controlling the FHB resistance in PI 672538. We further detected two major QTLs (Qfhs-2B, Qfhs-3B) from analysis of the resistance data and the PCR-amplified results using WinQTLCart 2.5 software. Qfhs-2B, flanked by Xbarc55-2B and Xbarc1155-2B, explained more than 11.6% of the phenotypic variation of the percentage of diseased spikelets (PDS), and Qfhs-3B, flanked by Xwmc54-3B and Xgwm566-3B, explained more than 10% of the PDS phenotypic variation in the F2:3 population. In addition, Qfhs-3B was different from Fhb1 in terms of the pedigree, inheritance, resistance response, chromosomal location, and marker diagnosis. We also detected QTLs for other disease resistance indices, including the percentage of damaged kernels and 1,000-grain weight, in similar chromosomal regions. Therefore, the FHB resistance of PI 672538 was mainly controlled by two major QTLs, mapped on 2B (FhbL693a) and 3B (FhbL693b). PI 672538 could be a useful germplasm for improving wheat FHB resistance.


Assuntos
Resistência à Doença/genética , Fusarium/fisiologia , Doenças das Plantas/imunologia , Locos de Características Quantitativas/genética , Triticum/genética , Mapeamento Cromossômico , Doenças das Plantas/microbiologia , Sementes/genética , Sementes/imunologia , Sementes/microbiologia , Triticum/imunologia , Triticum/microbiologia
5.
Neoplasma ; 64(6): 945-953, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28895422

RESUMO

The aim of this study is to explore the value of unenhanced magnetic resonance imaging (MRI), gadobenate dimeglumine injection (Gd-BOPTA)-enhanced MRI and diffusion-weighted imaging (DWI) in the diagnosis of intrahepatic mass-forming cholangiocarcinoma (IMCC). Totally 59 IMCC patients who underwent Gd-BOPTA-enhanced MRIs were recruited. The time-signal intensity curves and lesion periphery enhancement rates of the IMCC and liver parenchyma was drawn using apparent diffusion coefficient (ADC) values. The Gd-BOPTA-enhanced MRI showed that the peripheries of 30 lesions in the arterial phase exhibited irregular ring enhancement. However, lesions in the portal and delayed phases (which were gradually filled with a contrast agent), presented a patchy or latticed enhancement. Twenty-two lesions in the arterial and delayed phases exhibited uneven mild/moderate patchy enhancements with a progressive and centripetal lesion. Five lesions emerged from the arterial phase without any significant enhancement and had only gradual enhancement during the delayed phase. The remaining 2 lesions had a decreased mild enhancement, presented comparatively high signals and the lesion center had visible small spotted low signals. The DWI signals displayed a slightly high or high unevenness. Some lesion peripheries had a high signal but lesion centers displayed a relatively low or slightly low signal and irregular patches. There were significant differences between the ADC values of the lesion edge, lesion center and liver parenchyma. The IMCC detection rates of the Gd-BOPTA-enhanced MRI and DWI were higher than those of the unenhanced MRI. Our study demonstrated that both the Gd-BOPTA-enhanced MRI and DWI had higher accuracies rates than an unenhanced MRI. Furthermore, the hepatobiliary phase of IMCC plays an important role in the diagnosis and identification of IMCC constituents.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Humanos , Meglumina/análogos & derivados , Compostos Organometálicos
6.
Eur J Neurol ; 23(10): 1541-7, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27415600

RESUMO

BACKGROUND AND PURPOSE: Chronic syphilitic infection may lead to dementia. It is in general paresis (GP), which is the major late form of neurosyphilis, that cognitive impairment frequently occurs. The association between lipid metabolism and GP is unclear. METHODS: In this study, serum lipids were studied in 188 GP patients, in 241 syphilitic patients without neurosyphilis and in 539 healthy controls. The Mini-Mental State Examination (MMSE) was tested in all GP patients. Thirty-five GP patients had a follow-up evaluation 3 months after penicillin treatment. RESULTS: Significantly lower apolipoprotein A-I (apoA-I) levels were found in GP and in syphilitic patients without neurosyphilis compared to controls. In the 25-44-year-old groups, the male syphilitic patients without neurosyphilis had lower serum apoA-I levels and higher apolipoprotein B (apoB)/apoA-I ratios compared with female patients. A follow-up evaluation of 35 GP patients 3 months after penicillin treatment showed a significant positive correlation between increased apoA-I levels and MMSE scores. CONCLUSION: Abnormal apoA-I metabolism may be associated with the decline of cognitive performance. Long-term decrease of apoA-I level and higher apoB/apoA-I ratio may be contributing factors in syphilitic dementia. These results suggest a similar overlap between syphilitic dementia and lipid metabolism to that occurring in Alzheimer's disease.


Assuntos
Demência/sangue , Demência/etiologia , Metabolismo dos Lipídeos , Neurossífilis/sangue , Neurossífilis/complicações , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Zhonghua Yi Xue Za Zhi ; 96(36): 2893-2897, 2016 Sep 27.
Artigo em Chinês | MEDLINE | ID: mdl-27760634

RESUMO

Objective: To evaluate the efficacy of Bailemian capsule combined with self-help cognitive behavioral therapy (CBTI-SH) in treatment of chronic insomnia. Methods: Approved by the Ethics Committee of the hospital, 60 patients with chronic insomnia were randomly divided into two groups, the test group (Bailemian capsule combined with CBTI-SH) and the control group (CBTI-SH alone). Each group contained 30 cases. After 4 weeks for therapy, the sleep quality, mood and adverse reactions of treatment in patients were evaluated by sleep diary, sleep severity index scale (ISI), self-rating anxiety scale (SAS), self-rating depression scale (SDS) and treatment emergent symptom scale (TESS) respectively. The data were statistically analyzed. Results: The total effective rate in the test group was significantly higher than that of the control group (73.3% vs 46.7%, P<0.05). Compared to the control group, the sleep onset latency was significantly shorten [(38.3±13.1) vs (27.5±9.8) min, P<0.05], while the sleep efficiency were increased markedly [(76.6±5.7)% vs (80.5±6.6)%, P<0.05] in the test group. In the test group, the sleep onset latency, the total sleep time, the time in bed and sleep efficiency both improved significantly after treatment [(27.5±9.8) vs (56.2±19.4) min, (334.4±41.6) vs (310.8±31.7) min, (415.6±38.9) vs (446.9±39.9) min, (80.5±6.6)% vs (69.6±4.9)%, all P<0.05], while in the control group, the sleep onset latency, the time in bed and sleep efficiency also improved significantly after therapy [(38.3±13.1) vs (55.2±16.2) min, (430.4±32.6) vs (452.4±34.4) min, (76.6±5.7)% vs (69.9±5.2)%, all P<0.05]. After combined treatment, the SAS and SDS scores [(51.5±6.5) vs (55.0±5.8), (52.0±5.3) vs (55.3±4.4), both P<0.05] both decreased significantly than those of the control group, at the same time, the SAS and SDS scores decreased significantly after treatment in both the test group and the control group [(51.5±6.5) vs (61.5±4.8), (52.0±5.3) vs (60.2±4.5), (55.0±5.8) vs (62.5±3.7), (55.3±4.4) vs (62.2±3.7), all P<0.01]. Conclusion: The efficacy of Bailemian capsule combined with CBTI-SH in the treatment of chronic insomnia is more effective.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Transtornos de Ansiedade , Terapia Cognitivo-Comportamental , Comportamentos Relacionados com a Saúde , Humanos , Cooperação do Paciente , Sono , Resultado do Tratamento
8.
West Indian Med J ; 63(2): 167-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25303252

RESUMO

OBJECTIVE: This study investigates the change of endothelial cell morphology and function at the rabbit basilar bifurcations in response to sustained high blood flow after bilateral common carotid artery ligation. METHODS: Fifteen adult female New Zealand white rabbits were divided into experimental and sham control groups. The experimental group was subjected to bilateral common carotid artery ligation to increase the compensatory basilar artery flow. Basilar artery flow was monitored by transcranial Doppler after surgery. The endothelial cells at the arterial bifurcations were studied morphologically by electron microscopy and immunohistochemistry using ß-catenin antibodies. Basilar artery flow increased significantly following common carotid artery ligation. RESULTS: Early-stage basilar artery bifurcation aneurysms were present in all rabbits at three months after ligation. The endothelial cells changed from a fusiform to column shape at the basilar artery bifurcation. Gaps between endothelial cells of the experimental group appeared wider in the electron microscopic photographs compared with those of the control group. The expression of endothelial ß-catenin at the arterial bifurcations also decreased. CONCLUSION: This study is the first to present endothelial cell changes of basilar artery bifurcation in response to sustained high blood flow in rabbits. Endothelial cell impairment possibly initiates aneurysm formation.

9.
Artigo em Chinês | MEDLINE | ID: mdl-35610680

RESUMO

Objective: To explore the feasibility and short-term effect of tensor tympani muscle Tenotomy in the treatment of Meniere's disease under otoscope. The possible pathogenesis was discussed and our views were put forward. Methods: The clinical data of 9 cases of Meniere's disease treated by otoscopic Tenotomy were analyzed retrospectively, including 2 males, 7 females, 5 right ones, 2 left ones and 2 bilateral ones. The average age was (56.33± 10.56) years, ranging from 38 to 75 years. We evaluated intraoperative findings and short-term postoperative efficacy, respectively evaluated postoperative aural fullness, tinnitus and hearing recovery, and evaluated postoperative vertigo attack in a short time. Results: Nine patients were completed the operation under general anaesthesia and otoscopy, and no serious complications occurred. We found new pathological changes in tympanic cavity in some cases during operation. There were rupture of round window membrane in 1 case, severe fibrous hyperplasia near the round window membrane and vestibular window and adhesion with ossicular chain in 1 case, fibrous cord and membranous hyperplasia near vestibular window and round window membrane in 1 case, fibrous hyperplasia and adhesion near the round window membrane in 2 cases, membranous hyperplasia and adhesion around vestibular window in 1 case. No fibrous hyperplasia was found in 3 cases in the tympanic cavity. The round window membrane can be exposed in 4 cases and failed in 5 cases. After 3 months of follow-up, we found that we found that 5/5 cases of aural fullness disappeared, 2/2 cases of earache disappeared, 3/8 cases of tinnitus improved, 5/8 cases presented with improvement and no aggravation, 3/3 cases of hearing allergy improved, 4/9 cases of hearing improved, and 5/9 cases showed no improvement or decrease. 9 patients were followed up for 3 months, of whom 8 patients had no vertigo, one patient suffered from vertigo twice within 3 months after operation, and the patient suffered from rupture of round window membrane. Conclusions: Endoscopic Tenotomy for Meniere's disease has obvious curative effect and quick recovery after operation. During the operation, we find that most of Meniere's patients have fibrous cord hyperplasia near the inner ear window membrane, which may be the pathological manifestation after repeated rupture and repair of the inner ear window membrane. The vertigo of Meniere's disease may be related to the destruction and repair of inner ear membrane structure caused by improper contraction or spasm of tympanic tensor muscle.


Assuntos
Doença de Meniere , Zumbido , Idoso , Feminino , Humanos , Hiperplasia/patologia , Masculino , Doença de Meniere/complicações , Doença de Meniere/cirurgia , Pessoa de Meia-Idade , Otoscópios/efeitos adversos , Estudos Retrospectivos , Tenotomia/efeitos adversos , Tensor de Tímpano/patologia , Tensor de Tímpano/cirurgia , Zumbido/complicações , Vertigem/etiologia
10.
Eur Rev Med Pharmacol Sci ; 24(24): 13056-13061, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33378058

RESUMO

OBJECTIVE: Based on the latest epidemic situation and field experience, this study aims to explore the correlation of computed tomography (CT) stages and blood glucose level in patients with novel coronavirus pneumonia (COVID-19). PATIENTS AND METHODS: The clinical data of first and multiple CT imaging re-examination and blood glucose levels from 62 confirmed cases of COVID-19 were collected for a retrospective analysis to determine the correlation between glucose level and CT-based staging. RESULTS: Of the 62 COVID-19 patients, 48 cases of early stage and 14 cases of advanced stage were found in the CT data of the first diagnosis. These 62 cases were currently under follow-up (17-32 days): 18 cases in early stage-resorption stage, 25 cases in early stage-advanced stage-resorption stage, 12 cases in advanced stage-resorption stage, 5 cases in early stage -advanced stage-severe stage-resorption stage, and 2 cases in advanced stage-severe stage-resorption stage. Among them, the CT of 14 patients with advanced stage at the first diagnosis showed multiple stage lesions (advanced stage + early stage) at the same time. Patients presented with statistically significant changes in blood glucose at early stage-resorption stage, early stage-advanced stage-resorption stage, advanced stage-resorption stage, and early stage-advanced stage-severe stage-resorption stage (p<0.05). However, no statistically significant alterations were observed in the glucose level of patients with advanced stage-severe stage-resorption stage (p>0.05). CONCLUSIONS: Alteration of blood glucose is positively correlated with CT-based staging of COVID-19. Blood glucose is of great value in clinical diagnosis of COVID-19 and in determining the stage and prognosis of this disease.


Assuntos
Glicemia/metabolismo , COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/metabolismo , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , SARS-CoV-2 , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
11.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 31(24): 1913-1918, 2017 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-29798315

RESUMO

Objective:To investigate the effect of CCR3 gene knockout on the proliferation, maturation and apoptosis of eosinophils (EOS) in mice. Method:Bone marrow cells from CCR3 gene knockout mice (experimental group) and wild-type mice (control group) were cultured in vitro and induced differentiation into mature EOS. EOS proliferation was observed by cell counting.Expression of degranulation protein mRNA was detected by qRT-PCR. EOS apoptosis was detected by Annexin V-FITC/PI double staining method. Result:①The number of cells on the 0-14 day of EOS cultured in vitro showed that the number of cells in the experimental group was less than that in the control group at tenth, twelfth, fourteenth days, and the proliferation was slower, the difference was statistically significant (P<0.01). ②The test results of EOS cells apoptosis showed that, under the condition of containing 10 ng/ml IL-5 or no IL-5, the apoptosis rate of EOS cells in experimental group was higher than that in normal control group, the difference between both groups was statistically significant (P<0.01). ③The expression results of ECP, EPO, MBP mRNA in EOS showed that the expression levels of ECP, EPO, MBP mRNA in the experimental group compared with the normal control group were reduced in varying degrees, the difference between both groups was statistically significant (P<0.05). Conclusion:Knockout CCR3 gene can inhibit the proliferation and maturation of EOS and promote its apoptosis, which provides a theoretical basis for CCR3 as a target gene to treat allergic rhinitis.


Assuntos
Técnicas de Inativação de Genes , Receptores CCR3/genética , Rinite Alérgica/genética , Animais , Apoptose , Proliferação de Células , Eosinófilos/metabolismo , Expressão Gênica , Camundongos , Camundongos Knockout , Rinite Alérgica/terapia
12.
Biochim Biophys Acta ; 1245(3): 439-47, 1995 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-8541324

RESUMO

The ocular lens is a transparent organ comprised of a highly concentrated and highly ordered matrix of structural proteins, called crystallins, which are probably the longest lived proteins of the body. Lens transparency is dependent upon maintenance of the short range order of the crystallin matrix. This transparency must be maintained for decades in the absence of normal protein synthesis or repair capacity. We present evidence here that alpha-crystallin, one of the major lens proteins, plays a central role in vivo in stabilizing the other crystallins and preventing uncontrolled aggregation of these progressively modified and aging molecules. alpha-Crystallin has previously been shown to suppress non-specific aggregation of denaturing proteins in simple binary systems through a chaperone-like activity. Our studies using soluble homogenates of monkey lenses demonstrate a strong resistance to heat induced non-specific aggregation when the complete complement of crystallins is present; in contrast, if alpha-crystallin is selectively removed prior to heating, the remaining crystallins undergo extensive non-specific aggregation as indicated by light scattering. When alpha-crystallin is present it complexes with denaturing proteins forming a soluble heavy molecular weight (HMW) fraction but no insolubilization is observed, while when alpha-crystallin is absent there is heavy insolubilization and no HMW formed. When intact monkey lenses were heated it could be demonstrated that soluble HMW was generated. Similar HMW protein appears in vivo in the human lens as a function of age. These findings suggest that the soluble HMW protein present in the human lens is the product of the chaperone-like function of alpha-crystallin and that under physiological conditions alpha-crystallin inhibits the uncontrolled aggregation of damaged proteins, thereby preventing the formation of light scattering centers and opacification of the lens.


Assuntos
Cristalinas/metabolismo , Cristalino/metabolismo , Animais , Humanos , Macaca mulatta , Chaperonas Moleculares/metabolismo , Temperatura
13.
J Mol Biol ; 298(2): 261-72, 2000 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10764595

RESUMO

The small heat-shock proteins (sHSPs) form a diverse family of proteins that are produced in all organisms. They function as chaperone-like proteins in that they bind unfolded polypeptides and prevent uncontrolled protein aggregation. Here, we present parallel cryo-electron microscopy studies of five different sHSP assemblies: Methanococcus jannaschii HSP16.5, human alphaB-crystallin, human HSP27, bovine native alpha-crystallin, and the complex of alphaB-crystallin and unfolded alpha-lactalbumin. Gel-filtration chromatography indicated that HSP16.5 is the most monodisperse, while HSP27 and the alpha-crystallin assemblies are more polydisperse. Particle images revealed a similar trend showing mostly regular and symmetric assemblies for HSP16.5 particles and the most irregular assemblies with a wide range of diameters for HSP27. A symmetry test on the particle images indicated stronger octahedral symmetry for HSP16.5 than for HSP27 or the alpha-crystallin assemblies. A single particle reconstruction of HSP16.5, based on 5772 particle images with imposed octahedral symmetry, resulted in a structure that closely matched the crystal structure. In addition, the cryo-EM reconstruction revealed internal density presumably corresponding to the flexible 32 N-terminal residues that were not observed in the crystal structure. The N termini were found to partially fill the central cavity making it unlikely that HSP16.5 sequesters denatured proteins in the cavity. A reconstruction calculated without imposed symmetry confirmed the presence of at least loose octahedral symmetry for HSP16.5 in contrast to the other sHSPs examined, which displayed no clear overall symmetry. Asymmetric reconstructions for the alpha-crystallin assemblies, with an additional mass selection step during image processing, resulted in lower resolution structures. We interpret the alpha-crystallin reconstructions to be average representations of variable assemblies and suggest that the resolutions achieved indicate the degree of variability. Quaternary structural information derived from cryo-electron microscopy is related to recent EPR studies of the alpha-crystallin domain fold and dimer interface of alphaA-crystallin.


Assuntos
Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/ultraestrutura , Animais , Proteínas Arqueais , Bovinos , Cromatografia em Gel , Microscopia Crioeletrônica , Cristalinas/química , Cristalinas/metabolismo , Cristalinas/ultraestrutura , Cristalografia por Raios X , Proteínas de Choque Térmico/metabolismo , Humanos , Lactalbumina/química , Lactalbumina/metabolismo , Lactalbumina/ultraestrutura , Mathanococcus/química , Modelos Moleculares , Peso Molecular , Maleabilidade , Estrutura Quaternária de Proteína
14.
Free Radic Biol Med ; 7(5): 499-505, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2558979

RESUMO

Crystallins are the soluble structural proteins that constitute approximately 90% of the dry mass of the eye lens. The present study attempts to elucidate possible mechanisms whereby the H2O2 present in the eye could contribute to the oxidative modification of lens crystallins. The data indicate that exposure of solutions of crystallins to H2O2 and EDTA-chelated iron leads to covalent crosslinking of polypeptides, loss of intrinsic protein fluorescence, and the generation of a novel fluorophor emitting in the 420 nm range. These changes closely mimic oxidative modifications that occur in lens proteins in vivo. Exposure of the proteins to H2O2 in the absence of chelated iron failed to generate detectable levels of these modifications. These findings are contrasted with earlier studies of lenses in organ culture where H2O2 alone produced marked damage while the further addition of chelated iron protected the lenses from oxidation.


Assuntos
Cristalinas/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Quelantes de Ferro/farmacologia , Animais , Bovinos , Cristalinas/metabolismo , Radicais Livres , Hidróxidos/farmacologia , Radical Hidroxila , Técnicas In Vitro , Oxirredução , Espectrometria de Fluorescência
15.
Curr Eye Res ; 6(5): 725-32, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3595182

RESUMO

Lens proteins from the guinea pig (Cavia porcellus) were found to be similar to those of other mammals with the exception of the presence of a previously undescribed constituent comprising about 10% of the total soluble lens proteins. This oligomeric protein is composed of polypeptides with apparent molecular weight of 38,000 and elutes from gel exclusion chromatography columns in the beta H-crystallin fraction. Following purification by ion exchange chromatography an antibody was raised against the protein. Using that antibody and antibodies specific for other crystallins we could detect no cross-reactivity between the guinea pig protein and any other reported lens crystallin. This protein, which we have named zeta (zeta)-crystallin, is the first reported mammalian lens crystallin which is not part of the alpha- or beta-gamma families of crystallins. Unlike all other known mammalian crystallins, which have little or no alpha-helical structure, zeta-crystallin is estimated to be approximately 30-40% alpha-helix.


Assuntos
Cristalinas/metabolismo , Cobaias/metabolismo , Animais , Fenômenos Químicos , Química , Cromatografia por Troca Iônica , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida
16.
Curr Eye Res ; 12(5): 433-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8344067

RESUMO

The distribution of glutathione-S-transferase (GST) activity was determined in frozen normal human lenses. The highest activity of GST was found in the peripheral and equatorial regions, whereas the lowest activity was found in the nucleus. Western blot showed that both mu and pi isoenzymes of GST were present in human lenses. This result is similar to that found in rat lenses. In addition, GST activity was analyzed in 50 lens epithelia which were obtained during cataract surgery. Twenty-seven lens epithelia showed no activity. Statistically significant association was found between cortical and mixed cortical--nuclear cataract and loss of GST activity. No association was found between pure nuclear cataract and loss of epithelial GST activity.


Assuntos
Catarata/enzimologia , Glutationa Transferase/metabolismo , Isoenzimas/metabolismo , Cristalino/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Eletroforese em Gel de Poliacrilamida , Epitélio/enzimologia , Humanos , Córtex do Cristalino/enzimologia , Núcleo do Cristalino/enzimologia , Pessoa de Meia-Idade
17.
Curr Eye Res ; 8(9): 883-90, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2791632

RESUMO

In this study, we compared the thiol/disulfide status and the protein profiles for a group of normal lenses (over 60 years old) and a group of age matched cataractous lenses. In agreement with previous reports we found that the severity of the lens opacity and the color of the nucleus correlated well with the decrease of soluble proteins and increase of guanidine insoluble proteins. However, the decrease of nonprotein thiols and protein thiols was associated only with the pigmentation of the lenses. We discovered that protein-thiol mixed disulfide profiles provided new information on the lens biochemical changes. In the normal lens, we found nearly 10% of the total nonprotein thiols bound to the protein. There were two species of protein-thiol mixed disulfides, protein-GSH and protein-cysteine with the former 3-4 times higher than the latter. In the cataractous lens the mean value of some species was elevated two-fold whereas in the noncataractous pigmented lens both protein-thiol mixed disulfides were elevated but the protein-cysteine species showed more drastic increase (three-fold in one case and 13-fold in another case). It is therefore concluded that the formation of protein-thiol mixed disulfides may play a more critical role in cataractogenesis than does protein-protein disulfide formation.


Assuntos
Catarata/metabolismo , Dissulfetos/metabolismo , Proteínas do Olho/metabolismo , Cristalino/metabolismo , Pigmentação , Compostos de Sulfidrila/metabolismo , Idoso , Idoso de 80 Anos ou mais , Glutationa/metabolismo , Humanos , Pessoa de Meia-Idade , Oxirredução , Ligação Proteica , Solubilidade
18.
Int J Biol Macromol ; 22(3-4): 263-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9650081

RESUMO

A recent paper by Plater et al. [20], showed that the mutation of a single phenylalanine residue F27R in mouse alpha B completely abolished the chaperone-like property of alpha-crystallin when assayed with insulin at 25 degrees C or with gamma-crystallin at 66 degrees C. We have produced the same mutation as well as some additional mutations in human alpha B-crystallin. Our data suggest that the F27R mutation effected the thermal stability of alpha B-crystallin making it unstable at temperatures > or = 60 degrees C. In agreement with the published work, at these temperatures the F27R human recombinant alpha B-crystallin does not protect the target protein from aggregation. When assayed with insulin or alpha-lactalbumin at 25 or 37 degrees C, however, there were no differences in the protective abilities between the native alpha B-crystallin or the F27R mutated human alpha B-crystallin. Several other multiple mutations involving proline residues were also produced. These mutations did not effect the chaperone-like properties of human alpha B-crystallin, but some of them did effect the native molecular weight size as judged by gel filtration chromatography.


Assuntos
Cristalinas/genética , Cristalinas/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutação Puntual , Animais , Sequência de Bases , Sítios de Ligação/genética , Bovinos , Dicroísmo Circular , Cristalinas/química , Primers do DNA/genética , Estabilidade de Medicamentos , Humanos , Técnicas In Vitro , Lactalbumina/química , Lactalbumina/metabolismo , Camundongos , Chaperonas Moleculares/química , Peso Molecular , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura
19.
Chin Med J (Engl) ; 105(2): 135-8, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1597073

RESUMO

The possibility of T2 values in the differentiation of local recurrence and irradiation fibrosis was studied prospectively in 36 patients with nasopharyngeal carcinoma (NPC) after radiotherapy. All the patients had a soft-tissue mass in the nasopharynx demonstrated by CT. Fourteen patients had tumor recurrence, 20 radiation fibrosis, 1 postradiation edema, and 1 inflammatory change. The control group consisted of 8 patients with untreated NPC. It was found that T2 was longer in patients with tumor than in patients with radiation fibrosis. We conclude that MRI may be used as a noninvasive method for differentiating radiation fibrosis from local recurrent NPC, but the prolonged T2 value of tumor is not specific and may be seen in radiation edema and infection.


Assuntos
Neoplasias Nasofaríngeas/diagnóstico , Nasofaringe/patologia , Recidiva Local de Neoplasia/diagnóstico , Lesões por Radiação/diagnóstico , Radioterapia/efeitos adversos , Adulto , Feminino , Fibrose/diagnóstico , Fibrose/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/radioterapia , Nasofaringe/efeitos da radiação , Estudos Prospectivos
20.
Zhonghua Jie He He Hu Xi Za Zhi ; 13(3): 138-40, 189, 1990 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-2249313

RESUMO

MRI anatomy of 15 normal chests and features of 24 patients with bronchogenic carcinoma confirmed by surgery or exfoliative cell examination of sputum were analysed. The authors preliminarily conclude that MRI is of remarkable diagnostic value in demonstrating tumor size, its location and extent, exhibiting the relationship between tumor mass and its surrounding such as greater vessel, trachea and bronchi and so forth. It is also more efficient in detecting hilar or mediastinal metastatic lymphadenopathy.


Assuntos
Carcinoma Broncogênico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Adenocarcinoma/diagnóstico , Adulto , Idoso , Carcinoma de Células Escamosas/diagnóstico , Feminino , Humanos , Pulmão/patologia , Metástase Linfática , Imageamento por Ressonância Magnética , Masculino , Mediastino/patologia , Pessoa de Meia-Idade
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